As wireless network infrastructure improves, the quantity and quality of information and services accessible via wireless access terminals is increasing rapidly. With the advent of 3G and emerging 4G wireless cellular networks, consumers can increasingly access a variety of multimedia content, browse the internet, access e-mail, etc. Wireless data can be transmitted to access terminals using a variety of wireless protocols, such as IS-2000, IS-856 (1xEV-DO), 802.11, and Bluetooth, among others.
In existing protocols, wireless data is divided into packets that are sent (usually sequentially) to the access terminal over an air interface. Generally, access networks transmit data to an access terminal in discrete timeslots, which the access terminal may allocate among a number of access terminals. Each access terminal may have, at a given point in time and for a given sector, a certain number of time slots in which to receive each packet. The number of timeslots may be a function of the network conditions between the access terminal and the access network (e.g., the quality of service over the air interface).
When the access terminal is receiving data from a cellular access network, the access terminal may travel between sectors of the access network. When this occurs, a handoff between sectors must be performed, so that the communication can continue in the sector into which the access terminal has moved. Under existing protocols, an access terminal generally waits until completion of current packet transmission (or until the allowed number of timeslots has passed) before handing off from a current serving sector to another sector. As a specific example, if the access terminal detects that a new sector has a better signal-to-noise ratio than its current sector, the access terminal must wait until it successfully receives the packet currently being transmitted or until the number of timeslots allowed for transmission of the packet have passed without success. The access terminal may then begin the handoff process.